What is the Name of My Star Polyhedron?

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In summary, the star polyhedron is made of a regular icosahedron with a regular tetrahedron on each of its faces. It is not a stellation of the great stellated dodecahedron.
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lugita15
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I made a certain star polyhedron out of Magnetix, and I'm trying to identify what its name is. It is formed by taking a regular icosahedron, and building a regular tetrahedron on each of its faces. Since an icosahedron has 20 faces, the resulting figure is a 20-pointed star. I've been looking in Wikipedia, which lists quite a lot of star polyhedra, but so far none of them match. The closest thing I could find was the great stellated dodecahedron, except that the great stellated dodecahedron has isosceles triangles as faces, while mine has equilateral triangles as faces.

Is there a name for my polyhedron, or has it not been named because the number of polyhedra are infinite?
 
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  • #2
Hi lugita15! :smile:

Does this help … http://mathworld.wolfram.com/IcosahedronStellations.html" ? :wink:
 
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  • #3
tiny-tim said:
Hi lugita15! :smile:

Does this help … http://mathworld.wolfram.com/IcosahedronStellations.html" ? :wink:
Unfortunately, I don't think that my polyhedron is a stellation of an icosahedron. The definition of stellation in mathworld is "the process of constructing polyhedra by extending the facial planes past the polyhedron edges of a given polyhedron until they intersect." This is not the case for my polyhedron. This is because faces of the tetrahedra do not lie in the same planes as any of the faces of the icosahedron.

In order to clarify what I am talking about, I have attached two pictures, one of a plain old icosahedron, and one of the star polyhedron I am trying to identify. As you can see, each of the faces of each of the tetrahedra (except, of course, the faces which coincide with the icosahedron faces) makes obtuse angles with icosahedron faces adjacent to it.

As I mentioned in my first post, the polyhedron I'm looking for is extremely similar to the great stellated dodecahedron, and is in fact a deformed version of the latter.

I apologize if my terminology is imprecise; I don't know much about 3-D geometry.
 

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FAQ: What is the Name of My Star Polyhedron?

What is a polyhedron?

A polyhedron is a three-dimensional geometric shape that is made up of flat, polygonal faces, straight edges, and sharp corners or vertices.

How can you identify a polyhedron?

To identify a polyhedron, you need to count the number of faces, edges, and vertices. A polyhedron must have at least three faces, three edges, and three vertices. Additionally, the faces must be flat and the edges must be straight.

What are some examples of polyhedrons?

Some common examples of polyhedrons include cubes, pyramids, prisms, and dodecahedrons. There are also many other types of polyhedrons with more complex shapes and names, such as icosahedrons and octahedrons.

How are polyhedrons different from other three-dimensional shapes?

Polyhedrons are different from other three-dimensional shapes, such as spheres or cylinders, because they are made up of flat faces and sharp corners. Other three-dimensional shapes do not have these characteristics.

Are there any real-life examples of polyhedrons?

Yes, there are many real-life examples of polyhedrons. Some examples include dice, buildings with triangular or rectangular roofs, and packaging boxes. Many crystals and minerals also have polyhedral shapes.

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